This invention has particular application in the reduction in electrical erosion phenomena such as spark erosion of electrodes, especially with regard to the center electrode or center wire of spark plugs and igniters in internal combustion and similar engines. In spark plugs, a gap is provided between the center and ground electrodes for the spark current from the coil to arc across. The shape and material of the electrodes, the gap width, and the temperatures and pressures existing in the combustion chamber determine the voltage that is necessary to produce a spark. The voltage needed for sparking is called the plug's voltage requirement. In general, an electrode which has sharp edges has a lower voltage requirement than one with flat or rounded edges. Sharp edges on the electrodes tend to concentrate ionization and thus lower the voltage requirement. Spark plug electrodes erode away with use; rounding off the edges and causing as much as a 20 to 30 percent increase in the voltage requirements. Erosion also widens the gap between the electrodes. Both of these changes increase the plug's voltage requirements and when the voltage required to produce a spark finally exceeds the output of the ignition system, the plug will no longer fire.